Four channel azimuth and two channel non-azimuth read-after-write longitudinal magnetic head

Abstract

A read-after-write head for four channel azimuth recording in one mode of operation and two channel non-azimuth recording in another mode of operation. Four forward write head gaps, four read head gaps, and four backward write head gaps are geometrically positioned within a rotatable and laterally indexable face plate of a recording head housing. The read and write heads gaps collectively provide four forward write channels, four read channels, and four backward write channels. During the azimuth mode of operation, the head is rotated to the preselected positive or negative azimuth angle and all of the read and write channels are utilized. During the non-azimuth, or vertical, mode of operation, write channels two and four are utilized in combination with read channels one and three to provide two-channel non-azimuth, or vertical, operation.

What is claimed is: 
     
       1. A read-after-write recording head for recording information onto and reading information from a magnetic tape storage medium, comprising: (a) a surface against which the magnetic tape storage medium is moving in one of a forward direction and a backward direction;   (b) a plurality of laterally spaced apart forward write head gaps including lower edges and upper and lower portions opening into said surface;   (b) a plurality of laterally spaced apart backward write head gaps including lower edges and upper and lower portions opening into said surface spaced apart from said forward write head gaps; and   (c) a plurality of laterally spaced apart read head gaps including lower edges opening into said surface and located between said forward and backward head gaps, said read head gaps extending generally parallel to and laterally offset from said forward and backward write head gaps.   
     
     
       2. The apparatus of claim 1, wherein said plurality of backward write head gaps are laterally offset from said plurality of forward write head gaps. 
     
     
       3. The apparatus of claim 1, wherein said plurality of read head gaps are unequally spaced apart from said plurality of forward write head gaps and said plurality of backward write head gaps. 
     
     
       4. The apparatus of claim 1, wherein a first one of said read head gaps is positioned in opposing relationship to both an upper portion of a first one of said forward write head gaps and a lower portion of a first one of said backward write head gaps; and wherein a second one of said read head gaps is positioned in opposing relationship to both an upper portion of a second one of said forward write head gaps and a lower portion of a second one of said backward write head gaps.   
     
     
       5. The apparatus of claim 1, wherein an angle between a line tangent to a lower edge of a first one of said forward write head gaps and a lower edge of a first one of said read head gaps and a line perpendicular to said lower edge of said first one of said forward write head gaps is substantially equal to an angle between a line tangent to a lower edge of first one of said backward write head gaps and a lower edge of said first one of read head gaps and a line perpendicular to said lower edge of sad first one of said backward write head gaps. 
     
     
       6. The apparatus of claim 1, wherein angles between lines tangent to said lower edges of said forward write head gaps and said lower edges of said read head gaps and lines perpendicular to said lower edges of said forward write head gaps are substantially equal to angles between lines tangent to lower edges of said backward write head gaps and lower edges of said read head gaps and lines perpendicular to said lower edges of said backward write head gaps. 
     
     
       7. A read-after-write recording head for recording information onto and reading information from a magnetic tape storage medium, comprising: (a) a surface against which the magnetic tape storage medium is drawn in a forward direction and in a backward direction;   (b) first, second, third, and fourth laterally spaced part forward write head gaps including upper and lower edges and upper and lower portions opening into said surface;   (b) first, second, third, and fourth laterally spaced apart backward write head gaps including upper and lower edges and upper and lower portions opening into said surface spaced apart from said forward write head gaps, said forward and backward write head gaps being laterally offset; and   (c) first, second, third, and fourth laterally spaced apart read head gaps including lower edges opening into said surface and located between said forward and backward head gaps, sad read head gaps extending generally parallel to and laterally offset from said forward and backward write head gaps and unequally spaced apart from said forward and backward write head gaps;   (d) wherein said first read head gap is positioned in opposing relationship to said upper portion of said second forward write head gap and said lower portion of said second backward write head gap;   (e) wherein said third read head gap is positioned in opposing relationship to said upper portion of said fourth forward write head gap and said lower portion of said fourth backward write head gap;   (f) wherein an angle between a line tangent to said lower edge of said first forward write head gap and said lower edge of said first read head gap and a line perpendicular to said lower edge of said first forward write head gap is substantially equal to an angle between a line tangent to said lower edge of said first backward write head gap and said lower edge of said first read head gap and a line perpendicular to said lower edge of said first backward write head gap;   (g) wherein an angle between a line tangent to said lower edge of said second forward write head gap and said lower edge of said second read head gap and a line perpendicular to said lower edge of said second forward write head gap is substantially equal to an angle between a line tangent to said lower edge of said second backward write head gap and said lower edge of said second read head gap and a line perpendicular to said lower edge of said second backward write head gap;   (h) wherein an angle between a line tangent to said lower edge of said third forward write head gap and said lower edge of said third read head gap and a line perpendicular to said lower edge of said third forward write head gap is substantially equal to an angle between a line tangent to said lower edge of said third backward write head gap and said lower edge of said third read head gap and a line perpendicular to said lower edge of said third backward write head gap; and   (i) wherein an angle between a line tangent to said lower edge of said fourth forward write head gap and said lower edge of said fourth read head gap and a line perpendicular to said lower edge of said fourth forward write head gap is substantially equal to an angle between a line tangent to said lower edge of said fourth backward write head gap and said lower edge of said fourth read head gap and a line perpendicular to said lower edge of said fourth backward write head gap.